EPSON R300 Printer

I've just installed my brilliant new printer and am very happy with it but I can't seem to get it to print to cd/dvd ? It spits out the disk and says the tray isn't set up properly ? Anyone else had this problem ? It's driving me mad as to what the problem is!All my settings are set-up right (my friend has one and his is fine ?Any help is appreciated,Thanx.